When conventionally manufacturing a semiconductor device, a flat panel display, or the like, various processes such as an etching process, a film forming process and a cleaning process are repeatedly performed on a front surface (main surface: circuit forming surface) of a substrate such as a semiconductor wafer or a liquid crystal substrate while the substrate is held by a substrate holding device.
When performing such various processes on the substrate, contaminants such as particles may adhere to a rear surface of the substrate, or protrusions may be formed on the rear surface of the substrate. These contaminants adhering to the rear surface of the substrate or the protrusions formed on the rear surface of the substrate may have adverse effect on the various processes for the substrate.
For the reason, by pressing and rotating a substrate processing scrubber against the rear surface of the substrate, such a cleaning process or a polishing process is performed on the rear surface of the substrate. Thus, the removal target such as the contaminants or the protrusions is removed from the rear surface of the substrate. This substrate processing scrubber includes a base connected to a rotation shaft; and a multiple number of scrubber main bodies annularly arranged on the base along a rotational direction of the base (see, for example, Patent Document 1).    Patent Document 1: Japanese Patent Laid-open Publication No. 2011-206867
As for such a conventional substrate processing scrubber, however, when removing the removal target from the substrate, the scrubber main bodies that are separately provided are rotated while being pressed against the rear surface of the substrate. Accordingly, the separate scrubber main bodies may be inclined against the substrate by a repulsive force applied from the substrate. As a result, it is difficult to effectively eliminate the removal target from the substrate.